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1.
Sci Total Environ ; 953: 176219, 2024 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-39265675

RESUMEN

African ecosystems are expected to be significantly affected by climate change, making it crucial to understand these changes for effective management. We provide a framework and application to assess ecoregional vulnerability to climate change, considering environmental exposure, sensitivity, and adaptive capacity. We assessed environmental exposure using projections for consecutive dry days, precipitation, and temperature changes. Sensitivity was determined based on forest fragmentation and grassland degradation. Adaptive capacity was represented by protected areas network and biodiversity intactness. These factors were combined to create overall vulnerability index and specific categories to guide management decisions. Under the SSP5 8.5 scenario, 16 % of ecoregions will be highly impacted by 2050, with vulnerable areas emerging in Montane forest-grassland and flooded savanna. Impacted ecoregions are disproportionately biodiverse. By intersecting the likely climate impacts and adaptive capacity, we highlight where conservation actions are needed to enhance the resilience of ecoregions to climate change.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , África , Biodiversidad , Bosques , Pradera , Monitoreo del Ambiente
2.
J Environ Manage ; 354: 120395, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367500

RESUMEN

Large-scale desertification combatting programs (DCPs) are crucial tools for addressing climate change and improving the ecological environment. Despite existing research having predominantly focused on assessing the ecological benefits of DCPs, the understanding of their impacts on surrounding socioeconomic aspects remains limited, particularly at the household level. To comprehensively evaluate the returns of DCPs, this study chose the representative desertification control area of the Gonghe Basin on the Qinghai-Tibet Plateau as the research region and identified the dual benefits in terms of ecological environment and socioeconomic gains. Firstly, two essential ecosystem services, carbon sequestration (CS) and wind erosion prevention (WEP), were assessed using the MODIS NPP dataset and the RWEQ model from 2001 to 2021. Household surveys were conducted in 36 villages across 14 townships within the Gonghe Basin to gain a deeper understanding of the residents' socioeconomic conditions. Through regression analysis, the study assessed the impact of DCPs on the regional ecological environment and household socioeconomic status. The research findings revealed significant improvements in CS and WEP across a significant portion of the study area from 2001 to 2021. Upon analyzing data from 401 household questionnaires, it was generally perceived by residents in the Gonghe Basin that the implementation of DCPs led to environmental improvements and increased their income levels. Further regression analysis revealed a significant impact of both natural factors and the extent of resident participation in the projects on the ecological environment surrounding the villages and on household socioeconomic aspects. With increased resident engagement in the projects, the likelihood of increased household income and life satisfaction was higher. The diverse array of DCPs implemented in the Gonghe Basin not only improved the regional ecological environment but also stimulated socioeconomic development. In future projects, it is imperative to consider regional characteristics, align ecological effects, ensure the sustainability of livelihoods, and maximize the role of social capital.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Tibet , Cambio Climático , Factores Socioeconómicos , China
3.
Artículo en Inglés | MEDLINE | ID: mdl-36901073

RESUMEN

The increase in population and economic development has made environmental issues more serious and threatens regional ecological security and sustainable development. Currently, most indicators in the related research field of ecological security tend to be socio-economic and neglect depicting the state of the ecosystems. This study, therefore, assessed the ecological security by constructing the evaluation index system embedded in the ecosystem service supply and demand based on the pressure-state-response model and identified the key obstacles to ecological security in the Pearl River Delta from 1990 to 2015. Our results showed that soil retention, carbon sequestration, and water yield increased with fluctuation except for grain production and habitat quality. The grain demand, carbon emission, and water demand increased sharply by 10.1%, 769.4%, and 17.5%, respectively. The ecosystem service supply areas were mainly located in the low hills, while the demand regions were mainly in the low plain areas. The ecological security index's decline in vitality was caused by the decrease in the pressure index, indicating that the ecological security showed an inevitable deterioration and increased pressure on the ecosystem. During the study period, the source of the five key obstacle factors changed from the state layer and response layer to the pressure layer. The accumulative degree of the five top obstacle factors was above 45%. Therefore, governments should grasp the key indicators to improve ecological security as this study provides the theoretical basis and scientific information for sustainable development.


Asunto(s)
Ecología , Ecosistema , Ríos , Conservación de los Recursos Naturales , Suelo , China
4.
Front Plant Sci ; 13: 1045290, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36388493

RESUMEN

Vegetation greenness is one of the main indicators to characterize changes in terrestrial ecosystems. China has implemented a few large-scale ecological restoration programs on the Qinghai-Tibetan Plateau (QTP) to reverse the trend of ecosystem degradation. Although the effectiveness of these programs is beginning to show, the mechanisms of vegetation degradation under climate change and human activities are still controversial. Existing studies have mostly focused on changes in overall vegetation change, with less attention on the drivers of change in different vegetation types. In this study, earth satellite observation records were used to robustly map changes in vegetation greenness on the QTP from 2000 to 2021. The random forest (RF) algorithm was further used to detect the drivers of greenness browning on the QTP as a whole and in seven different vegetation types. The results show that an overall trend of greening in all seven vegetation types on the QTP over a 21-year period. The area of greening was 46.54×104 km2, and browning was 5.32×104 km2, representing a quarter and 2.86% of the natural vegetation area, respectively. The results of the browning driver analysis show that areas with high altitude, reduced annual precipitation, high intensity of human activity, average annual maximum and average annual minimum precipitation of approximately 500 mm are most susceptible to browning on the QTP. For the seven different vegetation types, their top 6 most important browning drivers and the ranking of drivers differed. DEM and precipitation changes are important drivers of browning for seven vegetation types. These results reflect the latest spatial and temporal dynamics of vegetation on the QTP and highlight the common and characteristic browning drivers of vegetation ecosystems. They provide support for understanding the response of different vegetation to natural and human impacts and for further implementation of site-specific restoration measures.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36231508

RESUMEN

The Himalayan region is a fragile high mountain landscape where the population experiences acute vulnerability within a complex coupled human-natural system due to environmental, social, and economic linkages. The lack of significant regional and spatial knowledge of multi-faceted vulnerabilities hinders any potential recommendations to address these vulnerabilities. We systematically reviewed the literature to recommend mitigation interventions based on the region's socio-economic and ecological vulnerability research to date. We applied the PRISMA (Preferred Reporting of Items for Systematic Review and Meta-Analysis) criteria to search for results from four comprehensive databases. For our assessment, we compiled a final sample (n = 59) of vulnerability research papers to examine the vulnerability types, spatial variation, assessment methodology, and significant drivers of change. Our study represented all Himalayan countries, namely, India, Nepal, Pakistan, China, and Bhutan. More than half of the vulnerability studies were conducted in the central Himalayan region, a quarter in the western Himalayas, and a few in the eastern Himalayas. Our review revealed that the primary drivers of change were climate change, land use/land cover, and glacial lake formation. The vulnerability assessments in the Himalayan region primarily used social science methods as compared to natural science methods. While the vulnerability studies seldom assessed mitigation interventions, our analysis identified fourteen recommendations. The recommended interventions mainly included policy interventions, livelihood improvement, and adaptation measures. This study emphasized that sustainable development requires cross-sectoral interventions to manage existing resources and mitigate the confronting vulnerabilities of the region.


Asunto(s)
Cambio Climático , Lagos , Aclimatación , Humanos , India , Nepal
6.
Sci Total Environ ; 836: 155625, 2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35508233

RESUMEN

Excessive human activities destroy the structure and function of ecosystem and threaten sustainable development. As a typical resource-based area, Shanxi Province is facing an increasingly serious contradiction between ecosystem and sustainable development, with the overexploitation of resources. In view of this, the coupling coordination degree model was used to measure the association between sustainable development and ecosystem services (SDESs), and geographically and temporally weighted regression model was used to explore the correlation between SDESs and measure the correlation between ecosystem services (ESs) and sustainable development at the county level from 2000 to 2015 in Shanxi Province. The results showed an increase in the sustainable development level and all ESs except soil retention. The coupling coordination degree (CCD) of soil retention and sustainable development decreased, while other services increased. Habitat quality had the strongest negative correlation with sustainable development. There were obvious spatiotemporal heterogeneities in the CCD and correlation of SDESs, which is helpful for promoting regional sustainable development and optimize ecosystem decision-making.


Asunto(s)
Ecosistema , Desarrollo Sostenible , China , Conservación de los Recursos Naturales , Humanos , Suelo
7.
J Environ Manage ; 301: 113814, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34601349

RESUMEN

Ecosystem service flows are a research topic of significant interest, and exploring this topic may mitigate the shortcomings related to the spatial mismatches between supply and demand in the current ecosystem services studies. The Pearl River Delta (PRD) experiences a serious spatial mismatch in ecosystem services in particular the food supply, between the supply areas (hilly areas) and demand areas (central areas). Therefore, this study focused on the PRD as a case study to analyze change trends of food supply-demand ratio (FSDR) at city level, and depict the spatial flow path within and between cities from the perspective of ecosystem service flow with different threshold distance, using an enhanced two-step floating catchment area accessibility method. The results showed that the food demand significantly exceeded the supply, the budget was 3.58 million tons and FSDR was 0.49 in 2015. There were large discrepancies in the FSDR at the city level before and after when considering the ecosystem service flows. The FSDR of cities in the central areas increased 0.1%-30%, due to the ecosystem service flow from the low hilly areas. As delivery distances increased, the size of food flow decreased within cities and increased among cities. This led to a significant decline in the population living in severe undersupplied areas (FSDR<0.1) and oversupplied areas (FSDR>1), and an increase in undersupplied areas (0.1<FSDR<0.9). Our findings indicate that local governments would benefit from enhancing connections between supply and demand areas to meet the food demand of big cities. This study offers a comprehensive and realistic understanding of the physical situation of ecosystem service consumption by human beings, and provides decision-making information for optimize land use allocation.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Abastecimiento de Alimentos , China , Ciudades , Ríos
8.
J Environ Manage ; 255: 109925, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32063306

RESUMEN

The Bashang Plateau, which is an ecologically fragile agro-pastoral zone in Hebei Province in China, plays an important role in protecting the Beijing-Tianjin-Hebei region from wind and sand erosion. Over the last four decades, it has been the target of extensive afforestation campaigns to promote improved ecosystem services. Though the benefits and costs of afforestation and its effectiveness within forestry have been widely investigated, few studies have focused on local households' willingness to accept (WTA) compensation relating to afforestation policies. Moreover, despite their importance in ensuring effective afforestation policies, the factors influencing WTA values have seldom been examined. We administered a direct questionnaire survey of households on the Bashang Plateau and applied a contingent valuation analysis to estimate their WTA values for compensation associated with ecological protection policies. We obtained 249 valid questionnaires, evidencing a high response rate (92.22%). New indicators of factors influencing respondents' WTA has been conducted including social, economic and ecological aspects, especially the improvement of ecological factors which consists of respondents' perceptions regarding the importance of ES and their satisfaction levels, and other environmental awareness factors. Additionally, in the case where many studies performed only one single regression analysis, this study performed a two-stage regression analysis and compared the results with those obtained using the Tobit model. A reasonable compensation standard facilitates a positive relationship between economic development and protection of natural environments. The findings showed that a certain amount of compensation (approximately 477.91 CNY/mu/year) was likely to prompt households' participation in afforestation projects. Compared with compensation standards for other ecological projects, the reported standard for afforestation projects on the Bashang Plateau is low, indicating that there is room for improvement. High annual household incomes are a key factor influencing households' WTA regarding their participation in afforestation activities. The results also revealed households' environmental awareness. Among respondents who participated in afforestation, those who valued forests for protecting environments and improving ecosystem services opted for lower compensation amounts. Our findings contribute valuable inputs for formulating ecological compensation standards and can serve as a reference for analyses of WTA and factors that drive it in other similar economically backward and ecologically fragile regions.


Asunto(s)
Ecología , Ecosistema , Beijing , China , Conservación de los Recursos Naturales , Bosques
9.
Sci Total Environ ; 685: 786-794, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31238282

RESUMEN

Carbon emissions have become a global environmental problem in recent years. It is necessary to explore methods to improve the efficiency of energy consumption and minimize carbon emissions that accompany economic development and rapid urbanization. In this paper, we quantitatively measure the total factor carbon emission performance (TFCP) and the carbon emission mitigation potential (CMP) of 39 industrial sectors in the Beijing-Tianjin-Hebei (BTH) region from 2010 to 2016 by employing a stochastic frontier approach. The results show that the average TFCP value of the 39 industrial sectors in the BTH region was relatively low (0.7733). From 2010 to 2016, the TFCP increased in Beijing, decreased in Tianjin and held steady in Hebei. The entire level of TFCP in Hebei was the greatest, followed by Tianjin and Beijing. The CMP in the BTH region increased slightly during the period 2010-2016. The total CMP of the 39 industrial sectors in the BTH region was 11.03 × 108 t from 2010 to 2016. The industrial sectors were divided into four categories according to the relationship between TFCP and CMP. Belonging to the low TFCP-high CMP quadrant, the Manufacture of Nonmetallic Mineral Products sector and the Production and Distribution of Electric Power and Heat Power sector should attract more attention when formulating carbon reduction policies and related regulations. According to the results, we also present suggestions to strengthen green economic growth and regional sustainable development.

10.
ScientificWorldJournal ; 2013: 329187, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23970833

RESUMEN

It has been widely accepted that there is a close relationship between the land use type and water quality. There have been some researches on this relationship from the perspective of the spatial configuration of land use in recent years. This study aims to analyze the influence of various land use types on the water quality within the Chaohu Lake Basin based on the water quality monitoring data and RS data from 2000 to 2008, with the small watershed as the basic unit of analysis. The results indicated that there was significant negative correlation between forest land and grassland and the water pollution, and the built-up area had negative impacts on the water quality, while the influence of the cultivated land on the water quality was very complex. Besides, the impacts of the landscape diversity on the indicators of water quality within the watershed were also analyzed, the result of which indicated there was a significant negative relationship between them. The results can provide important scientific reference for the local land use optimization and water pollution control and guidance for the formulation of policies to coordinate the exploitation and protection of the water resource.


Asunto(s)
Lagos , Calidad del Agua , China
11.
J Environ Radioact ; 113: 1-7, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22595723

RESUMEN

Artificial Radiocaesium ((137)Cs) has been widely deposited over global soils. In this study, we measured (137)Cs activity concentrations in the soil samples taken from Jing-Jin-Ji Region, North China, during 2007-2008. The surface soil (0-20 cm) samples were collected from 452 sites in this region. The activity concentration of (137)Cs in the samples was measured using a GEM series HPGe (high-purity germanium) coaxial detector system (ADCOM-100). The main findings are as following. (1) The activity concentration of (137)Cs in surface soils in the region of study fluctuates within 0.3±0.1 to 12.9±0.4 Bq/kg with mean value of 3.7 Bq/kg. Compared to other regions located at roughly the same latitude, the (137)Cs activity is relatively low. The results indicate that there are no new inputs of the radionuclides into the area at that time and the data obtained could serve as baseline levels of (137)Cs in Jing-Jin-Ji Region. (2) Considering land use types, surface soil in woodland mostly shows high (137)Cs activities with rare natural erosion and anthropogenic activities, and the surface soil with relatively low (137)Cs activities appears in the areas of intensive anthropogenic activities, especially in the cities, river banks, reservoirs and the strongly eroded areas. The findings suggest that the varying distribution of (137)Cs activities in surface soil corresponds with land use types.


Asunto(s)
Radioisótopos de Cesio/análisis , Monitoreo del Ambiente/métodos , Contaminantes Radiactivos del Suelo/análisis , China
12.
Environ Manage ; 45(3): 488-501, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19536592

RESUMEN

The goal of this article is to understand strategies by which both the environmental and poverty alleviation objectives of PES programs can be achieved cost effectively. To meet this goal, we first create a conceptual framework to understand the implications of alternative targeting when policy makers have both environmental and poverty alleviation goals. We then use the Grain for Green program in China, the largest PES program in the developing world, as a case study. We also use a data set from a survey that we designed and implemented to evaluate the program. Using the data set we first evaluate what factors determined selection of program areas for the Grain for Green program. We then demonstrate the heterogeneity of parcels and households and examine the correlations across households and their parcels in terms of their potential environmental benefits, opportunity costs of participating, and the asset levels of households as an indicator of poverty. Finally, we compare five alternative targeting criteria and simulate their performance in terms of cost effectiveness in meeting both the environmental and poverty alleviation goals when given a fixed budget. Based on our simulations, we find that there is a substantial gain in the cost effectiveness of the program by targeting parcels based on the "gold standard," i.e., targeting parcels with low opportunity cost and high environmental benefit managed by poorer households.


Asunto(s)
Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/métodos , Ecosistema , Pobreza/prevención & control , China , Análisis Costo-Beneficio , Composición Familiar , Humanos , Modelos Econométricos , Modelos Teóricos , Población Rural
13.
Sensors (Basel) ; 8(2): 620-634, 2008 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-27879726

RESUMEN

In this paper we present and develop a new model, which we have calledDynamics of Land Systems (DLS). The DLS model is capable of integrating multiple datasources to simulate the dynamics of a land system. Three main modules are incorporatedin DLS: a spatial regression module, to explore the relationship between land uses andinfluencing factors, a scenario analysis module of the land uses of a region during thesimulation period and a spatial disaggregation module, to allocate land use changes froma regional level to disaggregated grid cells. A case study on Taips County in North Chinais incorporated in this paper to test the functionality of DLS. The simulation results underthe baseline, economic priority and environmental scenarios help to understand the landsystem dynamics and project near future land-use trajectories of a region, in order tofocus management decisions on land uses and land use planning.

14.
Ying Yong Sheng Tai Xue Bao ; 17(5): 867-72, 2006 May.
Artículo en Chino | MEDLINE | ID: mdl-16883817

RESUMEN

Ecological diversity refers to a combination of the richness and evenness of an investigation object. Based on this, the widely used model, Shannon model, and a recently developed model, Scaling ecological diversity model, were theoretically analyzed in this paper. It was indicated that Shannon model had many limitations, e. g., it could be available only when the number of each type of investigation object was more than 100, did not include any information of scale, and could not express the richness of diversity. In other words, Shannon model could only express the evenness of diversity. A case-study in Fukang of Xinjiang Uygur Autonomous Region showed that the richness and Shannon evenness were always resolution-dependent, while the ecotope diversity calculated by Scaling ecological diversity model was resolution-independent when the spatial resolution ranged from 30 m x 30 m to 150 m x 150 m, and strictly increased when the spatial resolution ranged from 150 m x 150 m to 480 m x 480 m.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ecología , Modelos Teóricos , China , Ecología/métodos , Ecosistema
15.
Ambio ; 34(6): 450-5, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16201216

RESUMEN

Along with its economic reform, China has experienced a rapid urbanization. This study mapped urban land expansion in China using high-resolution Landsat Thematic Mapper and Enhanced Thematic Mapper data of 1989/1990, 1995/1996 and 1999/2000 and analyzed its expansion modes and the driving forces underlying this process during 1990-2000. Our results show that China's urban land increased by 817 thousand hectares, of which 80.8% occurred during 1990-1995 and 19.2% during 1995-2000. It was also found that China's urban expansion had high spatial and temporal differences, such as four expansion modes, concentric, leapfrog, linear and multi-nuclei, and their combinations coexisted and expanded urban land area in the second 5 y was much less than that of the first 5 y. Case studies of the 13 mega cities showed that urban expansion had been largely driven by demographic change, economic growth, and changes in land use policies and regulations.


Asunto(s)
Economía , Población Urbana , China
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